Britain is set for a "a summer like no other," London mayor Boris Johnson predicted ahead of the official handover of the Olympic Flame.
London 2012 chairman Lord Coe, the Princess Royal and and Olympics minister Hugh Robertson, head up a delegation which will see the flame "laid to rest" at the Acropolis this evening and handed over to London at the Panathenaic Stadium in Athens on Thursday evening.
Mr Johnson, in one of his first public official appointments since being re-elected this month, also makes the journey to receive the sacred flame and bring it to London.
He said: "Bringing the Olympic flame back from its ancient home in Greece is a hugely symbolic moment which will ignite people's hopes and aspirations for what will be a summer like no other.
"As well as providing a fantastic spectacle of sport the London Games are giving us a once in a lifetime chance to make London an even better place to live, work and do business in.
"We must grasp the huge opportunities that they present to build on the investment we are making to deliver thousands of new jobs, new homes and new infrastructure that are already delivering solid economic growth in our great city."
The British delegation flies back on Friday evening, landing at RNAS Culdrose in Cornwall where they will attend a special ceremony welcoming the flame.
A 70-day relay, involving 8,000 torchbearers covering 8,000 miles, will then bring the flame to east London's Olympic Stadium and the opening of the Games on July 27.